Doc add section and fix documentation compile errors

[EmmaRenauld]

Create the whole-pipelines section.

Add figure 1 to Antoine's tutorial.

Fix some doc errors.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 72.45%. Comparing base (798134e) to head (5f6dff4).
⚠️ Report is 3 commits behind head on master.

❌ Your project status has failed because the head coverage (72.45%) is below the target coverage (75.00%). You can increase the head coverage or adjust the target coverage.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #1255      +/-   ##
==========================================
- Coverage   72.45%   72.45%   -0.01%     
==========================================
  Files         293      293              
  Lines       25184    25184              
  Branches     3526     3526              
==========================================
- Hits        18248    18247       -1     
+ Misses       5446     5445       -1     
- Partials     1490     1492       +2     

Components	Coverage Δ
Scripts	75.27% <ø> (-0.02%)	⬇️
Library	∅ <ø> (∅)

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